SRK2000 STMicroelectronics, SRK2000 Datasheet
SRK2000
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SRK2000 Summary of contents
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... ATX SMPS ■ 90+/92+ compliant server SMPS ■ Industrial SMPS Description The SRK2000 smart driver implements a control scheme specific to secondary-side synchronous rectification in LLC resonant converters that use a transformer with center-tap secondary winding for full-wave rectification. It provides two high-current gate-drive outputs, each capable of driving one or more N-channel Power MOSFETs ...
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... Application information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 5.1 EN pin: pin function and usage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 5.1.1 5.1.2 5.1.3 5.2 Drain voltage sensing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 5.3 Gate driving . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 5.4 Intelligent automatic sleep-mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 5.5 Protection against current reversal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 5.6 Layout guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 6 Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 7 Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 2/17 Pull-up resistor configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Resistor divider configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Remote on/off control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Doc ID 17811 Rev 2 SRK2000 ...
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... SRK2000 1 Pin description Figure 2. Pin configuration Table 2. Pin description n. Name 1 SGND DVS1 4 DVS2 5 GD2 7 GD1 6 PGND 8 Vcc SGND SGND DVS1 DVS1 3 3 DVS2 DVS2 4 4 Signal ground. Return of the bias current of the device and 0 V reference for drain-to-source voltage monitors of both sections ...
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... Pin description Figure 3. Typical system block diagram 4/17 Doc ID 17811 Rev 2 SRK2000 ...
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... SRK2000 2 Maximum ratings Table 3. Absolute maximum ratings Symbol Pin Vcc 8 Icc 8 Z --- DVS1,2_sk DVS1,2_sr Table 4. Thermal data Symbol R Max. thermal resistance, junction-to-ambient thJA Ptot Power dissipation @ T T Junction temperature operating range J T Storage temperature stg 3 Typical application schematic Figure 4 ...
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... EN = SGND DVS1 Vcc DVS1 -250 mV DVS1 680 kΩ from EN to Vcc R = 270 kΩ from EN to Vcc After sourcing I After crossing V Positive-going edge Below V EN_On Doc ID 17811 Rev 2 SRK2000 ; unless otherwise CC Min. Typ. Max. Unit 4.5 32 4.25 4.5 4.75 4 4.25 4.5 0. ...
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... SRK2000 Table 5. Electrical characteristics (continued) Symbol I Bias current EN Turn-off threshold selection V Selection threshold EN-Th I Pull-down current EN Gate drivers V Output high voltage GDH V Output low voltage GDL I Output source peak current sourcepk I Output sink peak current sinkpk t Fall time f t Rise time r V Output clamp voltage ...
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... CCOn for the drain voltage DVS1,2_Off < EN_Th (4.25 V typ.). CCOff turn-off threshold. The DVS1,2_Off − − Off = − Off = 680 kΩ in the first case and switched off and the enable function EN SRK2000 (= 0.36 1 set at EN_On ...
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... SRK2000 1 this threshold is exceeded the gate drivers GD1 and GD2 are enabled and the SR MOSFET is operated; otherwise, the device stays in an idle condition and the SR MOSFET in the off state. Using the pull-up resistor R to Vcc, therefore exceeding V Essentially, this results in enabling the gate-driving as Vcc exceeds V as Vcc falls below V are logic-level types ...
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... mV. DVS1,2_Off must definitely be higher than the maximum value of V EN_On Doc ID 17811 Rev − − 0.32 V). EN_Th -6 ·R1 4.555) < 0.32; EN_Th -6 ·R1 4.555) > 0.4; . SRK2000 : (= 0.40 V). ...
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... SRK2000 5.1.3 Remote on/off control Whichever configuration is used, since a voltage on the EN pin 45 mV below V disables the gate drivers, any small-signal transistor can be used to pull down the EN pin and force the gate drivers into an off state. Finally, it should be noted that during power-up, power-down, and under overload or short- circuit conditions, the gate drivers are shut down if the Vcc voltage is insufficient: < ...
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... DVS1,2_Off is crossed (in the second half of the conduction cycle) and DVS1,2_Off delay has a maximum value of 60 ns. PD_Off Doc ID 17811 Rev 2 DVS1,2_TH + V DVS 250 ns) is used after PD_On . Again, since the initial current is DS(on) DVS1,2_Off . The interlock logic, TH-ON SRK2000 (- , and ...
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... SRK2000 Figure 8. Typical connection of the SRK2000 to the SR MOSFET 5.3 Gate driving The IC is provided with two high-current gate-drive outputs (1 A source and 3.5 A sink), each capable of driving one or more N-channel Power MOSFETs. Thanks to the programmable gate-drive UVLO possible to drive both standard MOSFETs and logic level MOSFETs ...
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... They should be low-ESR, low-ESL types and located as close to the IC pins as possible. Sometimes a series resistor (in the tens) between the converter's output voltage and the Vcc pin, forming an RC filter along with the bypass capacitor, is useful in order to get a cleaner Vcc voltage. 14/17 Doc ID 17811 Rev 2 SRK2000 ) of the ON ...
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... SRK2000 6 Package mechanical data In order to meet environmental requirements, ST offers these devices in different grades of ® ECOPACK packages, depending on their level of environmental compliance. ECOPACK specifications, grade definitions and product status are available at trademark. Table 1. SO-8 mechanical data Dim ( ...
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... Revision history 7 Revision history Table 6. Document revision history Date 10-Aug-2010 08-Feb-2012 16/17 Revision 1 Initial release. Minor text changes to improve readability in features, on cover Chapter 5 page, and 2 Chapter 5.5: Protection against current reversal Added Document status promoted from preliminary data to datasheet. Doc ID 17811 Rev 2 SRK2000 Changes . . ...
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... SRK2000 Information in this document is provided solely in connection with ST products. STMicroelectronics NV and its subsidiaries (“ST”) reserve the right to make changes, corrections, modifications or improvements, to this document, and the products and services described herein at any time, without notice. All ST products are sold pursuant to ST’s terms and conditions of sale. ...